Hacking GameCube

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Encryption on GCN AR Codes

Encryption is a mask on data which may or may not contain more data itself.

Encrypted codes are formatted for use in the Action Replay. They look like this:
All Evidence Max
G12C-TMX0-WRT5C
G2ND-C1RJ-G4TZ1

Decrypted codes are in raw format and can be edited. They look like this:
All Evidence Max
00690E90 000004FF

Codes for the GCN AR are encrypted for a number of reasons, just the top line of every encrypted code does three things meant to prevent user error:

1. Tells what region the code is for.
   • USA [often called NTSC or NTSC-U]
   • EU [often called PAL]
   • Japan [sometimes called JP or NTSC-J]
2. Tells if the code has already been entered.
   • Each code has a unique ID among the codes for that game.
     GCNCrypt gives each code its own random ID and has such a small chance of overlapping at any random point that it wasn't even worth mentioning.
3. Tells what game the code is for via the "Game ID" which can be seen at the bottom of [#encryption_how_to GCNCrypt].

The encryption of the codes also allows the Action Replay to check for accuracy of what was entered beyond where it belongs. When a new code is entered into the AR it decrypts it, if it could not decrypt it then an "Invalid Code" error shows up.

How to Encrypt/Decrypt Codes

Encrypting and Decrypting codes for the GameCube Action Replay requires Parasyte's GCNCrypt program from the GCN Tools.
Note: Once a game's AR code is decrypted in GCNCrypt, if the Auto Identifier box is checked, it will set the Game ID and Region so any code can be changed or added then encrypted for the same game.

To decrypt an encrypted code, paste the encrypted code into the left text box in GCNCrypt then press the "Decrypt" button at the bottom. Output is on the right and can be copy/pasted onto the left for editing.
Many times after decrypting a code, the output won't be used. Hackers often decrypt codes from a game to automatically set the Region and Game ID for their new codes.
However, if a code was decrypted to be edited.. this is important:
Take the encrypted code, say this one:
All Evidence Max
G12C-TMX0-WRT5C
G2ND-C1RJ-G4TZ1

and then decrypt it in GCNCrypt, and this is the output:
All Evidence Max
01E22DC2 08000000
00690E90 000004FF

If the Auto Identifier box is checked (it should be) then copy the output over to the left and delete the top line of the code. This is done because- as said before- each time a code is encrypted, the top line gets added according to the Region and Game ID.
After that what's left is:
All Evidence Max
00690E90 000004FF

Now the code can be edited according to the AR code types below. After editing is done simply press "Encrypt" and copy the output on the right!

AR Code Types

The single-line GameCube ActionReplay code types are the first two hex digits of a decrypted code. GameCube's memory range is from 0x80000000 to 0x817FFFFF so if the code's address is greater or equal to 0x81000000 then the code type gets 0x01 added to it. For the addresses used in the code types below, "rrrrrr" signifies that address. These are of course, decrypted.

Type	Description
RAM Writes
RAM Write and Fill 8-Bit 00rrrrrr xxxxxxyy 16-Bit 02rrrrrr xxxxyyyy 32-Bit 04rrrrrr yyyyyyyy	xxxxxx: Number of bytes to write, zero-based (000000 writes yy to 0x80rrrrrr, 000001 writes yy to 0x80rrrrrr and to rrrrrr+0x01) yy: Byte to write. xxxx: Number of halfwords to write, zero-based (0000 writes yyyy to 0x80rrrrrr, 0001 writes yy to 0x80rrrrrr and to 0x80rrrrrr+0x02) yyyy: Halfword to write. yyyyyyyy: Word to write.
Struct Write (Pointers) 8-Bit 40rrrrrr xxxxxxyy 16-Bit 42rrrrrr xxxxyyyy 32-Bit 44rrrrrr yyyyyyyy	xxxxxx: Byte offset from pointer. yy: Byte to write to address ((pointer at 80rrrrrr)+offset) xxxx: Halfword offset from pointer. yyyy: Halfword to write to address ((pointer at 80rrrrrr)+offset*2) yyyyyyyy: Word to write to pointed address (value at the pointer address of 80rrrrrr)
RAM Fill and Slide 8-Bit 00000000 80rrrrrr 000000yy xxvvzzzz 16-Bit 00000000 82rrrrrr 0000yyyy xxvvzzzz 32-Bit 00000000 84rrrrrr yyyyyyyy xxvvzzzz	yy: Byte to write for fill and slide, beginning at address xx: Value increment (signed) vv: Number of bytes to write, zero-based zzzz: Address increment (signed) yyyy: Halfword to write for fill and slide, beginning at address xx: Value increment (signed) vv: Number of halfwords to write, zero-based zzzz: Address increment (signed) yyyyyyyy: Word to write for fill and slide, beginning at address xx: Value increment (signed) vv: Number of words to write, zero-based zzzz: Address increment (signed) TODO: Check and note what happens when vv is 00, 01, etc.
Signed Increment/Decrement 8-Bit 80rrrrrr 000000yy 16-Bit 82rrrrrr 0000yyyy 32-Bit 84rrrrrr yyyyyyyy Extended 86rrrrrr yyyyyyyy	Note: For signed values see "Signed Searches" in Generic Code Hacking. yy: Signed byte to add to the value at address. yyyy: Signed halfword to add to the value at address. yyyyyyyy: Signed word to add to the value at address. yyyyyyyy: Number to add to single precision (32-bit) float at address. Note: Number should be entered as a decimal value. TODO: Check exactly what kind of values this code type uses. (float, signed hex, unsigned hex, decimal[?], etc)
Conditional: If Equal
Next Line 8-Bit 08rrrrrr 000000yy 16-Bit 0Arrrrrr 0000yyyy 32-Bit 0Crrrrrr yyyyyyyy Next 2 Lines 8-Bit 48rrrrrr 000000yy 16-Bit 4Arrrrrr 0000yyyy 32-Bit 4Crrrrrr yyyyyyyy All until.. (see note) 8-Bit 88rrrrrr 000000yy 16-Bit 8Arrrrrr 0000yyyy 32-Bit 8Crrrrrr yyyyyyyy All Codes 8-Bit C8rrrrrr 000000yy 16-Bit CArrrrrr 0000yyyy 32-Bit CCrrrrrr yyyyyyyy	yy: Byte for comparison to the value at address. yyyy: Halfword for comparison to the value at address. yyyyyyyy: Word for comparison to the value at address. All until.. note: The conditional will activate all of the code's following lines until a "00000000 40000000" line is reached. (just put that line in the code when and where it's needed)
Conditional: If Not Equal
Next Line 8-Bit 10rrrrrr 000000yy 16-Bit 12rrrrrr 0000yyyy 32-Bit 14rrrrrr yyyyyyyy Next 2 Lines 8-Bit 50rrrrrr 000000yy 16-Bit 52rrrrrr 0000yyyy 32-Bit 54rrrrrr yyyyyyyy All until.. (see note) 8-Bit 90rrrrrr 000000yy 16-Bit 92rrrrrr 0000yyyy 32-Bit 94rrrrrr yyyyyyyy All Codes 8-Bit D0rrrrrr 000000yy 16-Bit D2rrrrrr 0000yyyy 32-Bit D4rrrrrr yyyyyyyy	yy: Byte for comparison to the value at address. yyyy: Halfword for comparison to the value at address. yyyyyyyy: Word for comparison to the value at address. All until.. note: The conditional will activate all of the code's following lines until a "00000000 40000000" line is reached. (just put that line in the code when and where it's needed)
Conditional: If Less (Signed)
Note: For signed values see "Signed Searches" in Generic Code Hacking.
Next Line 8-Bit 18rrrrrr 000000yy 16-Bit 1Arrrrrr 0000yyyy 32-Bit 1Crrrrrr yyyyyyyy Next 2 Lines 8-Bit 58rrrrrr 000000yy 16-Bit 5Arrrrrr 0000yyyy 32-Bit 5Crrrrrr yyyyyyyy All until.. (see note) 8-Bit 98rrrrrr 000000yy 16-Bit 9Arrrrrr 0000yyyy 32-Bit 9Crrrrrr yyyyyyyy All Codes 8-Bit D8rrrrrr 000000yy 16-Bit DArrrrrr 0000yyyy 32-Bit DCrrrrrr yyyyyyyy	yy: Byte for comparison to the value at address. yyyy: Halfword for comparison to the value at address. yyyyyyyy: Word for comparison to the value at address. All until.. note: The conditional will activate all of the code's following lines until a "00000000 40000000" line is reached. (just put that line in the code when and where it's needed)
Conditional: If Greater (Signed)
Note: For signed values see "Signed Searches" in Generic Code Hacking.
Next Line 8-Bit 20rrrrrr 000000yy 16-Bit 22rrrrrr 0000yyyy 32-Bit 24rrrrrr yyyyyyyy Next 2 Lines 8-Bit 60rrrrrr 000000yy 16-Bit 62rrrrrr 0000yyyy 32-Bit 64rrrrrr yyyyyyyy All until.. (see note) 8-Bit A0rrrrrr 000000yy 16-Bit A2rrrrrr 0000yyyy 32-Bit A4rrrrrr yyyyyyyy All Codes 8-Bit E0rrrrrr 000000yy 16-Bit E2rrrrrr 0000yyyy 32-Bit E4rrrrrr yyyyyyyy	yy: Byte for comparison to the value at address. yyyy: Halfword for comparison to the value at address. yyyyyyyy: Word for comparison to the value at address. All until.. note: The conditional will activate all of the code's following lines until a "00000000 40000000" line is reached. (just put that line in the code when and where it's needed)
Conditional: If Less (Unsigned)
Note: For unsigned values see "Signed Searches" in Generic Code Hacking.
Next Line 8-Bit 28rrrrrr 000000yy 16-Bit 2Arrrrrr 0000yyyy 32-Bit 2Crrrrrr yyyyyyyy Next 2 Lines 8-Bit 68rrrrrr 000000yy 16-Bit 6Arrrrrr 0000yyyy 32-Bit 6Crrrrrr yyyyyyyy All until.. (see note) 8-Bit A8rrrrrr 000000yy 16-Bit AArrrrrr 0000yyyy 32-Bit ACrrrrrr yyyyyyyy All Codes 8-Bit E8rrrrrr 000000yy 16-Bit EArrrrrr 0000yyyy 32-Bit ECrrrrrr yyyyyyyy	yy: Byte for comparison to the value at address. yyyy: Halfword for comparison to the value at address. yyyyyyyy: Word for comparison to the value at address. All until.. note: The conditional will activate all of the code's following lines until a "00000000 40000000" line is reached. (just put that line in the code when and where it's needed)
Conditional: If Greater (Unsigned)
Note: For unsigned values see "Signed Searches" in Generic Code Hacking.
Next Line 8-Bit 30rrrrrr 000000yy 16-Bit 32rrrrrr 0000yyyy 32-Bit 34rrrrrr yyyyyyyy Next 2 Lines 8-Bit 70rrrrrr 000000yy 16-Bit 72rrrrrr 0000yyyy 32-Bit 74rrrrrr yyyyyyyy All until.. (see note) 8-Bit B0rrrrrr 000000yy 16-Bit B2rrrrrr 0000yyyy 32-Bit B4rrrrrr yyyyyyyy All Codes 8-Bit F0rrrrrr 000000yy 16-Bit F2rrrrrr 0000yyyy 32-Bit F4rrrrrr yyyyyyyy	yy: Byte for comparison to the value at address. yyyy: Halfword for comparison to the value at address. yyyyyyyy: Word for comparison to the value at address. All until.. note: The conditional will activate all of the code's following lines until a "00000000 40000000" line is reached. (just put that line in the code when and where it's needed)
Conditional: If Bitwise AND
Note: For Bitwise AND see "AND" in Number Formats.
Next Line 8-Bit 38rrrrrr 000000yy 16-Bit 3Arrrrrr 0000yyyy 32-Bit 3Crrrrrr yyyyyyyy Next 2 Lines 8-Bit 78rrrrrr 000000yy 16-Bit 7Arrrrrr 0000yyyy 32-Bit 7Crrrrrr yyyyyyyy All until.. (see note) 8-Bit B8rrrrrr 000000yy 16-Bit BArrrrrr 0000yyyy 32-Bit BCrrrrrr yyyyyyyy All Codes 8-Bit F8rrrrrr 000000yy 16-Bit FArrrrrr 0000yyyy 32-Bit FCrrrrrr yyyyyyyy	yy: Byte for comparison to the value at address. yyyy: Halfword for comparison to the value at address. yyyyyyyy: Word for comparison to the value at address. All until.. note: The conditional will activate all of the code's following lines until a "00000000 40000000" line is reached. (just put that line in the code when and where it's needed)

Button Values

Value	Button
Big Endian (More Common)
Note: Values can be added together for use as button combos.
0x0000	No Buttons
0x0001	D-Pad Left
0x0002	D-Pad Right
0x0004	D-Pad Down
0x0008	D-Pad Up
0x0010	Z
0x0020	R (Digital Click)
0x0040	L (Digital Click)
0x0100	A
0x0200	B
0x0400	X
0x0800	Y
0x1000	Start
Little Endian (Less Common)
Note: Values can be added together for use as button combos.
0x0000	No Buttons
0x0001	A
0x0002	B
0x0004	X
0x0008	Y
0x0010	Start
0x0100	D-Pad Left
0x0200	D-Pad Right
0x0400	D-Pad Down
0x0800	D-Pad Up
0x1000	Z
0x2000	R (Digital Click)
0x4000	L (Digital Click)
GBA Face Buttons
Note: This is for games that use the GBA as a controller. Note: Values can be added together for use as button combos.
0x00	No Buttons
0x01	A
0x02	B
0x04	Select
0x08	Start
0x10	D-Pad Right
0x20	D-Pad Left
0x40	D-Pad Up
0x80	D-Pad Down

Using GCNrd to Create Assembly Hacks

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